Stanford develops a radio the size of an ant, draws power from electromagnetic waves

What is this? A radio for ants? Not so much for ants, but it’s certainly the size of an ant. Stanford engineer Amin Arbabian has managed to create a wireless radio just a few millimeters across that is so energy efficient that it doesn’t need a battery. Instead, it harvests power from the incoming electromagnetic waves. The extremely low cost and small size of this technology means you could soon be surrounded by tiny radio chips in an interconnected mesh network.

The Stanford radio chip is designed to compute, execute, and relay signals. What sets this technology apart is that it all happens on a single chip that doesn’t rely on any exotic materials or theoretical principles. Arbabian sees this chip as the possible missing link in the so-called Internet of Things. If you want your lightbulbs to be connected to your other devices, you don’t need a high-power wireless radio–this one would do just fine. It uses so little power a single AAA battery could power it for more than 100 years.

At the most basic electronic level, the components built into the Stanford radio are similar to a typical Bluetooth or WiFi radio, but much smaller and more efficient. The antenna is particularly notable as it’s one-tenth the size of a standard WiFi antenna. The receiving antenna is where wireless signals are utilized to generate power–probably through inductive technology. Eliminating the need for an external power source essentially means this solid state circuit has unlimited usable life.

Arbabian had 100 of these pint-sized radio chips fabricated for testing, and they work exactly as predicted. With a cost of just pennies per unit, it would be trivial to build them into any product you wanted to connect to your home network. Arbabian sees a future where one of these radios-on-a-chip will be scattered throughout a home every meter or so, making it into one big network.